Washington National Cathedral removed two stained glass windows last month. They depicted Robert E. Lee and Stonewall Jackson. The cathedral is just one of many places across the nation grappling with the role of Confederate images and monuments in the 21st century. The largest number of such monuments stand in Gettysburg, Pa., the site of one of the bloodiest battles in American history. From Gettysburg National Military Park, NPR's Quil Lawrence has this report.

PETER: We are met on a great battlefield of that war.

QUIL LAWRENCE, BYLINE: Ten-year-old Peter Tynan is a history buff, so he's reciting Lincoln's Gettysburg Address off a plaque at the edge of the park.

PETER: That government of the people, by the people, for the people...

LAWRENCE: Peter and his family spent the day touring the battlefield, which is largely preserved as it was in 1863, when the war turned for the Union in a horrific battle just up the hill from here. He sums it up.

PETER: A place that many a man died for the sake of liberty, republic's democracy, et cetera.

LAWRENCE: Statues started going up here over a hundred years ago. Now there's talk of taking some down. Peter's dad, also Peter Tynan, says the Confederate statue controversy came up during their tour. He says no.

PETER TYNAN: This site is more for the people that fought the battle. You know, you've got to learn from the history. And that's what they preserved this for. It'd be a travesty if they took down the monument.

SCOTT HANCOCK: I'm not advocating that the monuments be removed, although I'm not opposed to it.

LAWRENCE: Scott Hancock is a professor at Gettysburg College of history and Africana studies. Actually, he likes the statues...

HANCOCK: This one I love, one Confederate soldier with the battle flag who's laying on the ground, who's been wounded.

LAWRENCE: ...Like these 16-foot-tall soldiers from Mississippi...

HANCOCK: The other soldier's with his musket cocked back over his shoulder, looking like he's about to swing at somebody.

LAWRENCE: ...Until he reads the inscriptions.

HANCOCK: The inscription says, on this ground our brave sires fought for the righteous cause. And I think we need to ask, was their cause righteous?

LAWRENCE: Almost no one argues anymore - not in public - that slavery was a righteous cause. But some of the people who erected these statues argue the war wasn't about slavery. That rhetoric helped reconcile the North and South. But it wasn't accurate, says Eric Foner, a leading Civil War historian.

ERIC FONER: Gettysburg was the kind of symbol of what they called the reconciliationist view of the Civil War. Both sides were fighting for causes that they considered just.

LAWRENCE: That reconciliation, says Foner, left out black people. That was still true when many of these statues went up.

FONER: Many of them were put up as a in-your-face to the civil rights movement. You guys are demanding your rights? Well, looky here.

LAWRENCE: Historians including Foner helped design a visitor center at Gettysburg which opened in 2008. He hopes that it counteracts some of the "Gone With The Wind" romanticization of the war. There's an introductory film.

(SOUNDBITE OF ARCHIVED RECORDING)

MORGAN FREEMAN: In 1860, the South is largely an agricultural society based on slave labor.

LAWRENCE: Yes, that is Morgan Freeman narrating. But not everyone goes to the visitor center. Many more people come here to walk the hills and look at the statues, 1,300 statues mostly sponsored by the states that joined the war. More than half of them honor Confederate soldiers on horses or aiming rifles, standing along the actual battle lines where the soldiers fought and fell. Historian Scott Hancock says out here, it sometimes feels like the South won the war.

HANCOCK: You could go to the museum and then come out here on the battlefield and pretty much forget. I mean, these memorials are really impressive.

LAWRENCE: Lots of amateur historians do re-enactments at Gettysburg. Hancock and I happened upon a group preparing an artillery demonstration, setting up canvas tents.

BRUCE STOCKING: It's a living history program.

LAWRENCE: Bruce Stocking has been doing this for more than 40 years.

STOCKING: Today, for example, we're doing Confederate artillery.

LAWRENCE: Now, I don't ask him about the cause of the war, but that's what he talks about.

Is this battlefield a museum?

STOCKING: Yes, Gettysburg is a museum. A lot of things about the American Civil War - oh, the causes and this - really, when you look at it, it's a constitutional issue.

LAWRENCE: Scott Hancock, standing next to me, tries not to interrupt. He lets Bruce Stocking talk for almost four minutes straight.

STOCKING: Slavery aside and everything 'cause in the North and Pennsylvania...

LAWRENCE: But then he can't help himself.

HANCOCK: It's about slavery. And that's why if you go to the visitor center...

STOCKING: I deal with the individual soldier more than the politics. It would've happened the slave issue or not.

HANCOCK: I would not agree. Most historians would not agree.

LAWRENCE: Hancock is black, by the way. Stocking is white. Their argument stays polite even as the angry sound of lawnmowers makes them raise their voices a bit. They go on for half an hour, respectful. But it seems to be an alternative facts situation.

STOCKING: Read the accounts of the northerners, how amazed they were the many Confederate soldiers that were African-American that were captured here.

HANCOCK: That's just a myth. That's just not true.

STOCKING: I...

HANCOCK: It's not true.

STOCKING: There are...

HANCOCK: It is not true. You can't find records of it.

STOCKING: Well, sure you can.

LAWRENCE: No serious historian says blacks supported the Confederacy. But Google it; plenty of groups on the Internet do. And for some of them, the statues at Gettysburg are the perfect venue. This past July, a few hundred rallied here to pledge allegiance to the Confederate battle flag.

There's a 70-foot-high observation tower at the bottom of the Confederate line - great view. Signs point out landmarks. And here again Hancock wishes they could add some information.

HANCOCK: Could we put a sign on the west side of this tower just about how these mountains are part of the Underground Railroad and fugitive slaves were one of the reasons that the South seceded?

LAWRENCE: He knows this park is supposed to be about the battle and the soldiers, but the statues below are already about much more than that. The park is a history lesson not just about the Civil War. Quil Lawrence, NPR News, Gettysburg. Transcript provided by NPR, Copyright NPR.